Help picking DC on/off switches

I'm in the process of trying to build a battery powered trailer mounted speaker system and i've got nearly all the parts now except for power switches. I didn't think i'd have a problem with choosing some but after searching around the vast majority of switches seem to be rated for AC or 12 or 24VDC and the absolute highest DC rating i've found so far is 28V, the problem is that the highest voltage i'm using is a little under 36VDC so where do i find appropriate switches?
I've been getting helpful advice about the speaker project from someone on a forum called SpeakerPlans but they seem to think that i'd be fine using an on/off switch rated at 5A 12VDC despite the higher voltage requirements of my amplifier, i'm not very electronics literate but this doesn't make sense to me and i'm a bit worried about pushing too high a voltage through the switch and perhaps causing a fire or something.

I would prefer a rotary switch if possible as i used one on my old 12V speaker and i found that it's a lot less likely to catch on clothes and bodies and break or accidentally turn on while the speaker is being manhandled/transported about.
I have 2 circuits in my speaker setup, one is the 36V circuit powering the amplifier/speaker and the other is a 12V circuit powering a small mixer to boost the gain and tweak the sound, assuming i can find a switch capable of handling the 36V is it possible to have one switch that could be wired up to turn on both circuits at the same time?

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Downunder35m9 months ago

Just take any mains power rated switch that is capable of the amps you need.
The voltage does not really matter - it is the AMPS that kill contacts.
Biggest difference between good 12V and good 240V switches is the distance between the contacts to prevent arcing at high voltages.

...And then there are toggle switched that you buy on eBay which are rated for 6 amps, and they start melting at less than 2 amps... Melting.

If you buy from china without any certificates or real safety tests than of course you get what you paid for.
That is why some countries still operate shops for electrical supplies that sell stuff tested to the countries regulations - and with warranty.

Yup, I probably paid a dollar or two for ten of them... Luckily I have a big collection of switches that I've salvaged from old electronic devices.

If you want to see bad than check those mains adapters that come with chinese devices on a regular base.
There is a reason thy are added for free ;)
The contact between the actual prongs for your power point and the adapter springs on the other side is made by touch!
No screw, no clip, no spring mount...
Once the top and bottom are screwed together you might be lucky enough to get contact for a few weeks, or until you are dumb enough to try something above 1000W with them LOOOOL
Around Xmas we had 5 house fires in town.
Four of them were caused by asian adapters the last by a dumb house owner using over 20 chinese extension boards for the xmas lights.
To be safe from the rain he "installed" them all under the roof....

When it comes to electronics or electrics that actually need to operate properly at all times I won't buy cheap imports.
I mean why save 2 bucks on a switch from china if the long term problems cost much more.....

ambientvoid (author)  Downunder35m9 months ago

im working under the assumption that i need a 5A switch because that's what i was told by someone more knowledgeable than myself, but how do i work out the Amps that my circuits will be using so i can be sure i'm getting the correct thing? also would say a 10A switch be okay to use on a 5A circuit because i've only been able to find 4A, 10A and 20A switches so far and i would assume that getting a lower rated switch would be the less ideal option...?

As said: a higher rated switch won't harm you.
A too low rated switch can fail and overheat.